// Copyright 2018 The Fuchsia Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include <fbl/algorithm.h>
#include <fbl/unique_ptr.h>
#include <perftest/results.h>
#include <unittest/unittest.h>

// Add terminator to a string buffer registered with fmemopen().
static bool FixUpFileBuffer(FILE* fp, char* buf, size_t buf_size) {
    ASSERT_FALSE(ferror(fp));
    size_t data_size = ftell(fp);
    ASSERT_LT(data_size, buf_size);
    buf[data_size] = '\0';
    ASSERT_EQ(fclose(fp), 0);
    return true;
}

static bool test_json_output() {
    BEGIN_TEST;

    perftest::ResultsSet results;
    perftest::TestCaseResults* test_case =
        results.AddTestCase("results_test", "ExampleNullSyscall", "nanoseconds");
    // Fill out some example data.
    for (int val = 101; val <= 105; ++val) {
        test_case->AppendValue(val);
    }

    // Write the JSON output to a buffer in memory.
    char buf[1000];
    FILE* fp = fmemopen(buf, sizeof(buf), "w+");
    ASSERT_NONNULL(fp);
    results.WriteJSON(fp);
    ASSERT_TRUE(FixUpFileBuffer(fp, buf, sizeof(buf)));

    // Test the JSON output.
    const char* expected = R"JSON([{"label":"ExampleNullSyscall","test_suite":"results_test","unit":"nanoseconds","values":[101.000000,102.000000,103.000000,104.000000,105.000000]}])JSON";
    EXPECT_STR_EQ(expected, buf, "");

    END_TEST;
}

static bool test_summary_statistics() {
    BEGIN_TEST;

    perftest::ResultsSet results;
    perftest::TestCaseResults* test_case =
        results.AddTestCase("results_test", "ExampleNullSyscall", "nanoseconds");
    // Fill out some example data in a non-sorted order.
    test_case->AppendValue(200);
    test_case->AppendValue(6);
    test_case->AppendValue(100);
    test_case->AppendValue(110);

    perftest::SummaryStatistics stats = test_case->GetSummaryStatistics();
    EXPECT_EQ(stats.min, 6);
    EXPECT_EQ(stats.max, 200);
    EXPECT_EQ(stats.mean, 104);
    EXPECT_EQ(static_cast<int>(stats.std_dev), 68);
    // There is an even number of values, so the median is interpolated.
    EXPECT_EQ(stats.median, (100 + 110) / 2);

    test_case->AppendValue(300);
    stats = test_case->GetSummaryStatistics();
    // There is an odd number of values, so the median is not interpolated.
    EXPECT_EQ(stats.median, 110);

    END_TEST;
}

// Test escaping special characters in strings in JSON output.
static bool test_json_string_escaping() {
    BEGIN_TEST;

    char buf[1000];
    FILE* fp = fmemopen(buf, sizeof(buf), "w+");
    ASSERT_NONNULL(fp);
    perftest::WriteJSONString(fp, "foo \"bar\" \\ \n \xff");
    ASSERT_TRUE(FixUpFileBuffer(fp, buf, sizeof(buf)));

    const char* expected = "\"foo \\\"bar\\\" \\\\ \\u000a \\u00ff\"";
    EXPECT_STR_EQ(expected, buf, "");

    END_TEST;
}

BEGIN_TEST_CASE(perf_results_output_tests)
RUN_TEST(test_json_output)
RUN_TEST(test_summary_statistics)
RUN_TEST(test_json_string_escaping)
END_TEST_CASE(perf_results_output_tests)